A photo of the locomotive posted by the MBTA on Twitter showed the starboard side of the vehicle, with a large American flag decal — but it was backward, with the field of blue stars on the right side of the flag, not the left.

A number of people noticed the aberration, and wondered aloud: What gives?

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It turns out that there are some pretty complex rules about flag displays, and among them is the stipulation that flag decals on the side of a moving vessel — aircraft, train, car, bicycle — must be shown as if it is waving in the wind.

The National Flag Foundation, a nonprofit dedicated to increasing awareness of proper flag etiquette, has a lot to say about this.

“When looking at the right side however, if the union [the 50 stars] is to the viewer’s left, it appears as though the flag is flying backwards when the vehicle or person is in motion,” the foundation writes on its website. “It would also place the flag in a position of being in retreat as the vehicle or person moves forward.”

“To alleviate this problem . . . flags painted on aircraft must face the direction of the flight, so as to be aerodynamically and aesthetically correct.”

The same, they say, goes for trains.

A transportation reunion

Call it an appearance from the ghosts of transportation secretaries past.

Earlier this month, MassDOT hosted a symposium with the Intelligent Transportation Society of America, focused on the subject of technology in transportation. The headline event: A reunion of nine former state transportation secretaries.

The talk went about an hour over schedule — they had been waiting awhile to get some things off their chests, it seemed — and talk ranged from gentle jabs at their fellow ex-secretaries to sweeping statements about the future of transportation investment, damning indictments of the Massachusetts Legislature, and frank revelations.

“I think technology is nice — I teach in a place that cares about it — but I think money is nicer. . . . We’ve got big problems, and it’s going to take big moves to solve them.”

Richard Taylor (1991-1992), on the economic benefits of transportation infrastructure

“But for the Ted Williams Tunnel, and but for the Silver Line and other infrastucture, [the Innovation District] would not be in the position that it is today. . . . We’ve not found a way to get — I don’t want to say ‘repaid,’ but at least get some kind of financial recognition for the benefit beyond transportation that we bring to the economy.”

James Kerasiotes (1992-’97),on controversial transportation projects

“The Central Artery/Tunnel Project has taught us that you can do something controversial . . . you can do something that half of the people will agree with you on and half the people don’t . . . and in the end, you try to find a way through. But regardless of the bumps and the bruises, the work that was done during the course of the project was worth it. The one thing that we can’t do is shy away from that in the future. Thinking big is a good thing.”

Patrick Moynihan (1998-’99), on the era of E-ZPass

“I can remember former [transportation secretary] Jim Aloisi and I having a conversation back in the mid-90s, and him saying, ‘One day, you’re going to be able to have this little thing in your car that will be able to drive through the tolls without ever having to stop.’ And I said, ‘Jim, come on.’ I was knocked out by fax machines in those days.”

Kevin Sullivan (1999-2002), on state funding for transportation

“You can only raise MBTA fares so many times. We really need the Commonwealth of Massachusetts to step up, and to put more resources from the general fund into the MBTA’s budget.”

James Scanlan (2002-2003),on driving habits

“I think we have too many cars on the road. I think one of the things we have to do is get people out of their vehicles and have more incentives for public transportation.”

Bernard Cohen (2007-2008),on keeping up with maintenance costs

“The longer you wait, the more you pay — as a result of inflation, as a result of the greater level of deterioration of your assets. It really does make sense to do things sooner rather than later if you can take the long view of things.”

James Aloisi (2009), on using new technology to cut costs

“We don’t have the resources. The Legislature is never going to have the political courage to give you all the money you need to do the job right. Don’t kid ourselves — there’s not a better secretary that’s going to come along, there’s not a better pitch that’s going to come along, there’s not a more courageous governor that’s going to make it happen. It’s not going to happen. So you’ve got to figure out how to be entrepreneurial, how to do more with less.”

Jeffrey Mullan (2009-2011), on the need for user transportation fees, such as tolls

“I’ve sat in lots of Cabinet meetings about complicated funding problems that the Department of Health and Human Service is having, or the Department of Education. I realized that transportation, whether we like it or not, is not our number one priority. And so long as we’re in a limited fiscal environment, and you’re fighting with the Department of Children and Families for money . . . we’re going to lose that battle. What we really need to do is get user-based system, where people who use the system pay.”

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